Pros and Cons of Various
Different Building Systems/Materials
All-steel bolt together modular homes
Ships to hawaii in flat packs for reasonable shipping costs
Bolt together for much lower labor costs
Once wall panels are installed, interior walls, floor, ceiling and exterior walls are finished. No dry wall drama!
They come fully insulated to code, approved by Hawaii bldg depts
No cutting or welding, any doors and windows you want
Steel Is factory made and rust free- galvalum coated, silicone polyester paint
Quiet and comfortable thermally
Put as many as you want together, no limit on sq footage
Not so good properties:
forklift required for a few days to assemble basic modules
Not familiar to most contractors or builders
There is trim where the 20' modules join together
Comes in 8' x 20' size only
Wood frame – conventional “stick” construction
Lots of skilled labor very familiar with the process
Good choice if near salt spray from the ocean
Very even in terms of thermal performance, ie the entire structure pretty much expands and contracts together consistently with heat and cold. Wood siding is naturally insulating from the hot sun and the cold, especially with insulation inside the walls and painted a light color. Most people choose roofing materials that are good looking, but cause the home to get very hot. Attic insulation, cool roof coatings and solar powered attic fans can effectively counteract the suns heat. Wood homes are very quiet and comfortable to live in. Repairs and modifications are performed quite easily compared to other building materials. Wood is not difficult to cut and fasten. Also good acoustic performance- ie generally good at canceling out sound. Wall studs generally do not separate from the siding- steel frame homes can have this problem.
Wood homes generally experience less moisture condensation inside the walls. This is due to woods ability to insulate. However, west facing walls can experience condensation. Heat reflective coatings can overcome this problem quite effectively. T1-11 wood siding and OSB wood siding are generally not attractive to termites, and hold up quite well in humid climates. Believe it or not, wood homes score high in most areas. This is why it is the number one choice in most areas. We strongly recommend additional borite treatment applied to all frame members before closing up walls on the inside of your structure. Most people do not do this, we find that unacceptable. We still think that AAC (aerated autoclaved concrete) is the very best, see why on this page below.
Not so good properties:
Termites eat wood. If you treat with additional borite after framing, you can greatly increase your odds against termite infestation and damage, but there is that underlying anxiety about the possibility of termites- subterranean being the worst kind. We feel that wood homes done right are a far better choice than steel frame homes, and certainly in Hawaii’s humid climate.
It often takes a long time to get the roof and exterior siding on, and so rain cancels progress building during this phase of construction.
Wood can rot from excessive moisture, and dry rot can also occur. Elastomeric waterproofing coatings applied to problem areas can prevent this problem quite well.
Bottom line- wood homes are a very good choice, better than most other systems, but we like AAC best.
AAC- Aerated, autoclaved concrete
As a recommended buildiing system the good properties are overwhelmingly present for AAC. Engineers and architects worldwide have embraced this material, and so it is the fastest growing system in the world. There are over 30 factories worldwide. Read more about it here.
Superior thermal performance in a single wall system. AAC is full of evenly spaced hydrogen bubbles caused by a reaction of aluminum powder with calcium hydroxide and water which produces millions of 1/62” – 1/8" hydrogen bubbles, causing the material to expand its volume by twice of its pre volume, imparting its lightweight and thermal insulating qualities. During a setting time of 30 Minutes – 4 hours, the hydrogen escapes and is replaced by air. These tiny, evenly spaced bubbles delivers incredible insulative performance in a single wall system. Single wall structures go up quicker!
The best fire rating of any material on the planet.
Outstanding acoustic performance- you can hardly hear anything in the next room, it deadens sound very well, and the home is only single wall.
Fast to build-
our 2’ x 3’ x 4” blocks are approx 75 lbs each, and 2 people can easily lift them into place and glue together using polyurethane construction adhesive.
Electrical wires are morticed inside of channels easily cut by a simple router.
Plumbing strategies depend on the homes design. Most often, PEX systems are employed, and often times, studded steel plumbing walls are constructed to make things easier where there is a lot of plumbing. Often times, supply water is run inside of the slab via pex pipes, or you can locate supply lines and vent pipes on the outside of the walls if you wish. You can also run vent pipes up thru the block walls themselves.
Termites do not eat it, it does not rust or rot.
AAC does not spall- ie the metal inside of the blocks does not rust and cause the material to spall or crack and bust off like conventional concrete and hollow tile structures do. AAC is flexible, if steel were to rust inside the blocks or panels, it would simply compress the AAC material slightly, it will not crack or bust like rigid concrete does. This alone is an overwhelming testament to this incredible material.
Not so good properties:
Some people claim it harbors fungus and mold, but this is easily prevented by the inexpensive, thinset/silica sand finish applied on the outside. We spray drywall mud on the inside to give it a smooth finish. If you did not do these processes, it would harbor mold and fungus because it is porous, even more so than CMU blocks or concrete, but if you seal it properly, this issue is an non-issue. The AAC we import is certified, and manufacturing is constantly supervised by personnel licensed by the original factory in Germany. The bldg dept has made mandatory changes in how one does the electrical, and
those changes has significantly raised the cost of the home. They are great
homes, the cost is quite a bit more than most other home systems. Read more about AAC here.
Shipping Container structures
Very quick to build your home or structure- we can build out quite a bit so it arrives ready for structural, electrical, plumbing and foundation inspections straight from us. Even if we don’t do any build-out, it arrives with a roof overhead from day one, which allows you to work inside if the weather is not cooperating. No other system has a roof overhead until you build one, which takes time, and you lose a lot of time if the weather is wet, which happens often on the Big Island of Hawaii. Govt and corporate clients find containers to be very cheap for them compared to building from scratch because their costs designing from scratch are incredibly prohibitive. This fact has increased demand for containers significantly.
Strong and transportable, stackable and very configurable- many design options, but not as flexible as other systems due to limited sizes of containers. It is best to not cut containers because the corners are a big part of their strength.
Reasonable project cost if kept simple, and using designs that make sense. Not all designs make economic sense. We can cut to the chase for you, just ask for our help.
Not so good properties:
Metal that is not galvanized rusts, and containers are not galvanized. We recommend using new containers so you are not chasing rust forever, and so inspectors don’t give you grief over dents. You need to be proactive dealing with rust by keeping containers painted with the proper paint, treating rust properly and fixing dents so bldg inspectors don’t fail you at inspections. Steel of any kind is not recommended if your location is near the ocean with on-shore winds due to corrosive salt spray.
Shipping modified containers inter-island is very expensive. Trucking and placement is not cheap either, and shipping container costs are going up constantly due to high demand from Govt, Military and Corporate entities using containers to build structures and for storage worldwide.
Limited design flexibility due to limited container lengths and widths. Building with 20s is very expensive, we recommend using only 40s or 45s. We can ship 40’ high-cubes to neighbor islands for next to nothing because we supply containers for big box houses to ship their cargo in, so 40’ hi-cubes are the way to go with us on the neighbor islands as well as oahu. 20s are expensive everywhere compared to 40s, so unless you cannot get 40s onto your property due to a tight driveway or other logistical reasons, you really should build with 40s, specifically 40’ hi-cubes, which have a 9’ ceiling height compared to an 8’ ceiling height on standard containers. 20s only come in standard height now.
Containers only come 8’ wide on the outside, 7’ 9” on the inside. By the time you insulate and drywall, the interior width is only about 7’ 5”. Doing double-wide structures means you pay for metal that you cut out, which also costs you in labor money or labor time if doing these cutouts yourself. Of course you can use the cut-out metal, which is why designs where you separate containers apart and truss a roof over everything make a lot of sense for many reasons, but one important reason related to this discussion is that you can use that cutout metal to weld across those spans for an all-metal structure. This is why we say some designs make sense, and others do not. Ask us for our expert advise on container structures.
Conclusion- Even though container structures have a lot of not so good properties, there are a lot of designs that make sense, are quick to build out, and thus can be time and cost effective. It is recommended to do as little welding as possible because welding burns the oil out of metal, making it much more prone to rust. It is imperative that you immediately prime and finish paint all welds within 30 minutes from the time the welds are completed. We are not prejudiced at all, we recommend the building system that we think makes the most overall sense for you and your application. You are the boss, so in the end, we build what you want us to build.
Light-gauge steel frame with OSB, T1-11 or Hardy siding
Termites do not eat steel (not yet at least!) Many insurance companies offer lower premiums on steel frame homes, but homeowners insurance costs are generally not worth considering in this debate.
You can build walls and other elements in a warehouse or other area out of the weather and sun. Steel-frame walls are lighter than those made of wood, so you can truck sections to building site and assemble quickly. This reduces materials left on-site, thus reducing theft potential, and can speed up the construction process.
Galvanized frame members fare pretty well against rust if you are careful to paint all your cuts with the proper paint. Steel is not recommended near the ocean, especially areas with prevailing onshore wind.
Not so good properties:
Steel frame structures are not even in terms of thermal performance, ie the frame expands and contracts at a different rate compared to the wood-based siding. This can cause screws that hold the siding to your frame to release, causing siding sometimes to not be secured completely to the frame in places. This can really be a problem if your labor strips screws that hold your siding to the frame. Steel frame homes lose about 37% of its insulating performance because steel conducts heat about 300 times faster than wood! Heat reflective coatings on west facing walls outside can overcome a lot of this problem, but those coatings cost money. They are great for any structure, but with steel frame, you almost have to do this on west facing walls. Acoustic performance is not as good as wood frame homes at canceling out sound.
Condensation occurs more easily vs wood frame homes. Condensation can drip down on your steel track and cause rust where the studs meet the lower track. You can minimize condensation and the bad effects of it by applying a heat reflective coating on your west facing walls, and properly ventilating those walls. Keeping the temperature inside your home as close to the temperature outside minimizes condensation. For those who have had a rough time in the past with termites, steel frame offers more peace of mind regarding termite damage. You should always exercise due diligence and research carefully your building environment conditions and the performance of the various building systems/materials before making a decision on what kind of system you want to build with. This is where we can really help you.
Steel frame structures are considered by those favoring it as being stronger than wood frame homes. Steel frame is put together with screws, which adds to the frames strength, but we do not feel that the difference is as great as the steel industry claims it is. Steel frame members are more consistent, but lumber is not all warped and crooked either. A properly constructed wood frame home is strong, we do not think steel is vastly superior to wood in earthquakes and hurricanes. Either system can be put together well or not, and the quality of your materials can be good or not good. More importantly- the quality of your labor makes all the difference for sure. We feel that overall, wood frame homes are vastly superior to steel, especially in hawaii’s humid climate and the hot sun's effect on those west facing walls. That said, we will build whatever you want us to build. You are the boss.
Heavy gauge steel frame with steel exterior walls
Frame and exterior walls are both steel, so they expand and contract evenly.
Steel buildings are strong, and built on a slab, they can fare better in hurricanes
and earthquakes generally speaking, if constructed and designed to handle high
winds and seismic load. These days, hawaii’s bldg and planning depts. are requiring higher performance in all structures, but simply meeting code does not mean you are protected for sure. We recommend over-building if you can afford it. Violent weather is now the norm worldwide. We are certified builders representing the best steel structure manufacturer in the USA. Their engineers are licensed in all 50 states, and engineered plans with engineer review and stamp are included in all bldg purchases, as well as the best follow-thru and customer support in the industry on the ground in hawaii.
Steel buildings can be less costly to build, especially if you are constructing a warehouse. That is why you see so many heavy frame steel warehouses everywhere, even though the cost of steel keeps rising.
The steel bldgs we engineer are made of the finest, most pure steel you can obtain, and is coated in galv-alum and painted with polyester-silicone paint, this is the best process in the industry. Our bldgs are warranted against rust for 25 years, and will last hundreds of years if you keep them coated on schedule, especially the roof. Our standing seam roofs have no punctures anywhere, unlike conventional steel roof systems that have screws penetrating the roof everywhere. Steel roofs are very long lasting if you re-coat them before the paint wears down to the primer. Now the paint has ceramic particles imbedded in it, resulting in significantly cooler roofs compared to conventional paint. We do recommend additional heat reflective coatings to keep heat and therefore A/C costs down, but doing this voids your warranty, so you need to decide what Is more important. Putting down 3-4 coats of Hawaiian sunguard or silicone elastomeric reduces heat by a huge degree, and can make the difference between misery and total comfort with much lower utility costs. We can help you make informed, intelligent decisions, eliminating doubt and frustration with no pressure what so ever, it is what we do!
Not so good properties:
Steel is getting expensive, and is expensive to ship to Hawaii. If you are bldg a warehouse, you still cannot beat an all-steel bldg cost wise.
Steel structures are hot, and conduct heat about 300 times faster than wood. What saves you in this regard is heat reflective paints now being used in the steel industry, and you can insulate your bldg even more by applying additional heat reflective coatings to the point where your bldg will perform thermally as good as a wood structure.
All-steel homes are expensive- heavy gauge steel frames require steel studs secured to the heavy frame, and the process is more time consuming.
If you like the idea of building a steel home, we think a good solution is using conventional light gauge steel studs with steel panels affixed to the studs vs using a heavy gauge steel frame. This is a cost-effective building system.
Steel will rust if you let the coating get down to the primer, and chasing rust is a nightmare. You need to be very proactive in maintaining your all-steel structure, especially the roof. Have you ever seen a steel roof that the owner let go? This is very foolish and expensive. Steel can work well, but you need to do things right, and maintain it properly. This is true of any bldg system.
Affordable Portable Housing 808-859-5740